OkHttp is principled and avoids being overly configurable, especially when such configuration is
to workaround a buggy server, test invalid scenarios or that contradict the relevant RFC.
Other HTTP libraries exist that fill that gap allowing extensive customisation including potentially
invalid requests.

Example Limitations

* Does not allow GET with a body.
* Cache is not an interface with alternative implementations.

        assertNotNull(key1);
        assertNotNull(key2);
        assertNotEquals(key1, key2);

        // Verify both cache entries exist
        DirectoryCacheEntry entry1 = directoryLeaseManager.getCacheEntry(dir1);
        DirectoryCacheEntry entry2 = directoryLeaseManager.getCacheEntry(dir2);

        assertNotNull(entry1);

      // code should be unreachable with correctly implemented Futures.
      // Cancel this future and return.
      // At this point, inputFuture is cancelled and outputFuture doesn't exist, so the value of
      // mayInterruptIfRunning is irrelevant.
      cancel(false);
      return;
    } catch (ExecutionException e) {
      // Set the cause of the exception as this future's exception.

func (sys *BucketMetadataSys) RemoveStaleBuckets(diskBuckets set.StringSet) {
	sys.Lock()
	defer sys.Unlock()

	for bucket := range sys.metadataMap {
		if diskBuckets.Contains(bucket) {
			continue
		} // doesn't exist on disk remove from memory.
		delete(sys.metadataMap, bucket)
		globalBucketMonitor.DeleteBucket(bucket)
	}
}

// Set - sets a new metadata in-memory.
// Only a shallow copy is saved and fields with references

    return Iterators.all(iterable.iterator(), predicate);
  }

  /**
   * Returns the first element in {@code iterable} that satisfies the given predicate; use this
   * method only when such an element is known to exist. If it is possible that <i>no</i> element
   * will match, use {@link #tryFind} or {@link #find(Iterable, Predicate, Object)} instead.
   *

	}

	var users4 []User
	DB.Joins("inner join pets on pets.user_id = users.id AND pets.name = ?", user.Pets[0].Name).Joins("join accounts on accounts.user_id = users.id AND accounts.number = ?", user.Account.Number+"non-exist").Where("users.name = ?", user.Name).First(&users4)
	if len(users4) != 0 {
		t.Errorf("should find no user when searching with unexisting credit card, but got %v", len(users4))
	}

	var users5 []User

    /**
     * Returns the value of a specific attribute.
     *
     * @param name the name of the attribute to retrieve
     * @return the attribute value, or {@code null} if the attribute doesn't exist
     * @throws NullPointerException if name is null
     */
    @Nullable
    String attribute(@Nonnull String name);

    /**
     * Returns an immutable list of all child nodes.
     *

		t.Fatalf("Unexpected failure with %v", errorCodes.ToAPIErr(s3Err))
	}

	if !owner {
		t.Fatalf("Expected owner to be 'true', found %t", owner)
	}

	_, _, s3Err = checkKeyValid(req, "does-not-exist")
	if s3Err != ErrInvalidAccessKeyID {
		t.Fatalf("Expected error 'ErrInvalidAccessKeyID', found %v", s3Err)
	}

	ucreds, err := auth.CreateCredentials("myuser1", "mypassword1")
	if err != nil {

     */
    private void updateConnectionMetrics() {
        // Clean up metrics for connections that no longer exist
        connectionMetrics.entrySet().removeIf(entry -> {
            String key = entry.getKey();
            boolean exists = connections.stream().anyMatch(conn -> getConnectionKey(conn).equals(key));
            return !exists;
        });
    }

    /**
     * Get detailed health statistics
     */

		defer ticker.Stop()
		var exit bool
		for !exit {
			select {
			case <-ticker.C:
			case <-ctx.Done():
				exit = true
			}
			metaMu.Lock()
			meta := *mc.meta
			meta, err = o.updateMetacacheListing(meta, rpc)
			if err == nil && time.Since(meta.lastHandout) > metacacheMaxClientWait {
				cancel()
				exit = true
				meta.status = scanStateError